JP2007092894A - Belt with helical teeth and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a configuration of a belt with helical teeth capable of satisfactorily reducing thrust force generated when driving and having a satisfactory bending fatigue property. <P>SOLUTION: This belt with helical teeth is provided with at least a back part 2 composed of an elastic body in which a plurality of core wires 4s, 4z, etc. are buried and a tooth part 3 like helical teeth. In this case, the core wire 4s formed by S twisting and the core wire 4z formed by Z twisting are arranged in the back part 2 by arranging them alternately and in parallel. The number of twisting of the core wire whose direction of twisting coincides with the direction of twisting of tooth trace in the tooth part 3 (a core wire 4Z formed by Z twisting in the selected drawing) is different from the number of twisting of a core wire whose direction of twisting is reverse to the direction of twisting of tooth trace (a core wire 4S formed by S twisting). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a configuration of a toothed belt in which a lotus tooth is formed and a manufacturing method thereof.

In Patent Document 1, in a helical tooth timing belt having a configuration in which a core wire is embedded in a belt main body, the inclination of the core wire is set in the direction opposite to the inclination of the belt streak with respect to the belt traveling direction, and the belt traveling reference is longitudinally set. As a reference, a helical timing belt is disclosed in which an S-twisted core wire is used when the belt tooth inclination is right-up and left-down, and a Z-twist core wire is used when the belt tooth inclination is left-up and right-down. According to Patent Document 1, according to the above configuration, it is possible to cancel the thrust force due to the twisting of the belt teeth and to prevent the vibration due to the friction between the side surface of the belt and the inner surface of the flanged pulley.
Japanese Patent No. 3513788 (FIG. 2 etc.)

In Patent Document 2, a plurality of core members each having a fine line are arranged in parallel, and the outer periphery of these core members is coated with a polymer material to form an endless ring, and at the inner surface side, a comb is formed. In the toothed belt, a toothed belt is disclosed in which the directions of the cores are made the same, and the directions of the cores and the twist directions of the helical teeth are the same. . According to Patent Document 2, according to the above-described configuration, it is possible to cancel the thrust for moving the toothed belt in the thrust direction by the force for eliminating the twist of each core material.
JP-A-10-153240 (FIG. 3 etc.)

Patent Document 3 is a helical tooth belt composed of a synthetic resin back part, a tooth part, and a core wire, and the twist angle of the core wire and the helical tooth angle are opposite to each other, and the helical tooth angle is 5 to 15 °. The structure which made the twist angle of the core wire 15 to 2 degrees is disclosed. According to Patent Document 3, according to the above configuration, it is possible to prevent the belt from being displaced and to prevent the durability from being deteriorated due to contact wear on the flange.
Japanese Patent Laying-Open No. 2005-161665 (FIG. 7)

  As described above, Patent Documents 1 and 3 and Patent Document 2 are completely opposite ideas about how to set the twist direction of the core wire in relation to the inclination of the belt teeth in order to cancel the thrust force. Is disclosed.

  Further, even if either Patent Document 2 or Patent Documents 1 and 3 are theoretically correct, the thrust force based on the force to untwist the core wire is considerably larger than the thrust force resulting from the inclination of the helical teeth. Therefore, if the number of twists of the core wire is determined so as to generate a thrust force commensurate with the thrust force caused by the helical teeth, the number of twists of the core wire must be reduced, and the twist of the core wire becomes insufficient. As a result, the bending fatigue of the belt deteriorates. Therefore, it becomes difficult to use the belt for a small-diameter pulley.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to a first aspect of the present invention, there is provided a helical toothed belt configured as follows. It includes at least a back portion made of an elastic body in which a plurality of core wires are embedded, and a helical tooth portion. In the back portion, the S-twisted core wire and the Z-twisted core wire are alternately arranged so as to be adjacent to each other. The number of twists of the core wire whose twist direction coincides with the twist direction of the teeth of the tooth portion is different from the number of twists of the core wire whose twist direction is opposite to the twist direction of the teeth.

  With this configuration, the thrust force can be offset appropriately by twisting the core wire, and the number of twists of the core wire itself can be secured, and the bending fatigue can be improved.

  Specifically, the helical toothed belt can be configured as follows. When the inclination of the tooth portion is configured to rise to the left and to the left when the belt running direction is the longitudinal reference, the number of strands of the Z-twisted core wire is larger than the number of strands of the S-twisted cord. To do. Alternatively, when the inclination of the tooth portion is configured to rise to the left and to the right when the belt running direction is the longitudinal reference, the number of strands of the S-twisted core wire is greater than the number of strands of the Z-twisted core wire. There are also many configurations.

  With this configuration, it is possible to cancel the thrust force resulting from the inclination (twisting) of the helical teeth and the thrust force based on the difference in the number of twists, thereby reducing the thrust force when the belt is used.

  According to a second aspect of the present invention, there is provided a helical toothed belt configured as follows. It includes at least a back portion made of an elastic body in which a plurality of core wires are embedded, and a helical tooth portion. The core wire is obtained by twisting S-twisted yarn and Z-twisted yarn. The number of twists of the yarn in which the twist direction coincides with the twist direction of the teeth of the tooth portion is different from the number of twists of the yarn in which the twist direction is opposite to the twist direction of the teeth.

  With this configuration, the thrust force can be appropriately offset by twisting the yarn of the core wire, and the number of twists of the yarn itself can be secured, so that bending fatigue can be improved.

  Specifically, the helical toothed belt can be configured as follows. That is, when the inclination of the tooth portion is configured to rise to the left and to the left when the belt running direction is the longitudinal reference, the number of twists of the Z twist yarn is made larger than the number of twists of the S twist yarn. Alternatively, when the inclination of the tooth portion is configured to rise to the left and to the right when the belt running direction is the longitudinal reference, the number of twists of the S twist yarn is configured to be greater than the number of twists of the Z twist yarn. .

  With this configuration, it is possible to cancel the thrust force resulting from the inclination (twisting) of the helical teeth and the thrust force based on the difference in the number of twists, thereby reducing the thrust force when the belt is used.

  According to the third aspect of the present invention, the following method for manufacturing a helical toothed belt is provided. It includes at least a back portion made of an elastic body in which a core wire is embedded, and a helical tooth portion. A plurality of the core wires are alternately embedded in the back portion so that the S-twisted core wire and the Z-twisted core wire are adjacent to each other. The number of twists of the core wire whose twist direction coincides with the twist direction of the teeth of the tooth portion is made different from the number of twists of the core wire whose twist direction is opposite to the twist direction of the teeth.

  By this method, the thrust force based on the inclination of the tooth trace can be appropriately canceled by twisting of the core wire, and the number of twists of the core wire itself can be secured, and the bending fatigue property can be improved.

  In the above method for manufacturing a helical toothed belt, the following is preferable. It is possible to manufacture a plurality of types of helical toothed belts having different helical tooth inclinations, and according to the inclination of the tooth parts, the twist direction coincides with the twist direction of the tooth lines of the tooth parts. The difference between the number of strands of the core wire and the number of strands of the core wire whose twist direction is opposite to the twist direction of the tooth trace is changed.

  According to this method, a belt having teeth with various inclinations can be manufactured, and the thrust force at the time of driving can be appropriately canceled and reduced regardless of the inclination.

  According to the 4th viewpoint of this invention, the manufacturing method of the following toothed belt is provided. It includes at least a back portion made of an elastic body in which a core wire is embedded, and a helical tooth portion. A core wire in which an S twisted yarn and a Z twisted yarn are twisted is buried in the back portion. The number of twists of the yarn in which the twist direction coincides with the twist direction of the teeth of the tooth portion is different from the number of twists of the yarn in which the twist direction is opposite to the twist direction of the teeth.

  By this method, the thrust force based on the inclination of the tooth trace can be appropriately offset by twisting the yarn of the core wire, and the number of twists of the yarn itself can be secured, and the bending fatigue property can be improved.

  In the above method for manufacturing a helical toothed belt, the following is preferable. It is possible to manufacture a plurality of types of helical toothed belts having different helical tooth inclinations, and according to the inclination of the tooth parts, the twist direction coincides with the twist direction of the tooth lines of the tooth parts. The difference between the number of twists of the yarn and the number of twists of the yarn whose twist direction is opposite to the twist direction of the teeth is changed.

  According to this method, a belt having teeth with various inclinations can be manufactured, and the thrust force at the time of driving can be appropriately canceled and reduced regardless of the inclination.

  Next, embodiments of the invention will be described. FIG. 1 is a schematic view of a helical toothed belt according to an embodiment of the present invention.

  FIG. 1 is a schematic view of a helical toothed belt 1 viewed from the helical tooth forming side. In FIG. 1, the helical toothed belt 1 is configured as an endless transmission belt having a back portion 2 and a tooth portion 3. A plurality of core wires 4s, 4z,... Are embedded in the back portion 2 arranged on the belt outer peripheral side. The back part 2 and the tooth | gear part 3 are comprised from the elastic body which consists of rubber | gum, As this elastic body, chloroprene rubber (neoprene), styrene butadiene rubber, epichlorohydrin rubber, polyurethane rubber etc. can be considered, for example.

  The tooth portion 3 arranged on the belt inner peripheral side is formed with a helical tooth 5, and the helical line of the helical tooth 5 has a belt traveling direction (a direction along the belt axis C) as shown in FIG. It is tilted by an angle A so as to be right-up and left-down when the vertical belt running direction is used as a reference.

  In the present embodiment, four core wires 4s, 4z,... Are arranged in the back portion 2 at regular intervals. Specifically, two S-twisted core wires 4s and two Z-twisted core wires 4z are alternately arranged so that the S-twisted core wires 4s and the Z-twisted core wires 4z are adjacent to each other. Is arranged. As shown in FIG. 1, the number of twists of the Z-twisted core wire 4z is set larger than the number of twists of the S-twisted core wire 4s.

  In addition, as a method of forming the helical tooth 5 of the tooth portion 3, for example, an elastic body corresponding to the tooth portion is placed on a mold in which teeth and grooves are alternately arranged and pressed from above. It is possible to type. And the magnitude | size of the inclination angle A of the tooth | gear part 3 (the said helical tooth 5) or the inclination direction of the helical tooth 5 can be changed variously by replacing | exchanging said metal mold | die suitably. Then, the helical toothed belt 1 can be manufactured by laminating the elastic body and the elastic body corresponding to the back portion 2 with the core wires 4s, 4z,.

  The effect by the above structure is demonstrated. That is, in the helical toothed belt 1 of the present embodiment, since the S strands and the Z strands 4s, 4z,... Are alternately arranged, the force ( Most) are canceled out between the adjacent core wires 4s and 4z. Therefore, the thrust force based on the twist of the core wire itself can be suppressed.

  In addition, since there is a difference in the number of twists of the S twisted core wire 4s and the Z twisted core wire 4z, by canceling the thrust force based on the difference in the twist number with the thrust force due to the inclination of the helical teeth, The thrust force generated in the helically toothed belt 1 when used around the pulley can be effectively reduced.

  Further, since the thrust force for canceling the thrust force due to the helical teeth is generated by the difference in the number of twists of both the cores 4s and 4z, the number of twists of both the cores 4s and 4z is not reduced. The bending fatigue property of the belt 1 can be improved.

  Specifically, in the present embodiment, as shown in FIG. 1, the inclination of the tooth portion 3 is set to be right-up and left-down, and a Z-twisted core that is a core wire in which the twist direction and the twist direction of the tooth line coincide with each other. The number of twists of the wire 4z is larger than the number of twists of the S-twisted core wire 4s whose twist direction is opposite. Thereby, the thrust force resulting from the inclination (twist) of the tooth trace and the thrust force based on the difference in the number of twists can be offset, and the thrust force when using the belt can be reduced.

  That is, as a result of the force to untwist the Z-twisted core wire 4z exceeding the force to untwist the S-twisted core wire 4s, the belt is slightly twisted in the direction to untwist the Z-twisted core wire 4z. As a result, the belt enters in a form that is not perpendicular to the pulley axis but is slightly inclined, thereby causing the belt to move toward one end (left side) in the pulley axis direction. On the other hand, since the inclination of the tooth portion 3 is set to be right-up and left-down, when the outer peripheral teeth are wound around the drive pulley that is left-up and right-down, the belt is pushed by the pulley teeth and the other end side in the axial direction of the pulley Try to move to the right. As described above, as a result of the thrust forces canceling each other, the belt 1 is prevented from being displaced (moved) in the axial direction, thereby effectively preventing unnecessary contact of the belt side surface and the occurrence of vibrations. Can do.

  Further, by manufacturing the belt 1 so that the difference in the number of twists is made different in accordance with the inclination of the helical tooth 5, the belt 1 is caused by the inclination of the tooth line during driving regardless of the inclination of the helical tooth 5. The thrust force to be canceled can be offset appropriately.

  The above effects are supported by the following experiments conducted by the inventors of the present application. In this effect confirmation experiment, first, a belt having a plurality of S-twisted core wires arranged at equal intervals on the back was prepared, and the number of twists of the S-twisted core wires was 4.0 TPI. Then, when the belt was wound around a pulley and driven, a large thrust force was generated. However, the belt was good in terms of bending fatigue.

  Next, the same experiment was performed on the belt in which only the S-strand core was disposed in the same manner as described above, and the number of twists of the core was 2.0 TPI. Then, although the thrust force generated during driving could be reduced, the bending fatigue property was greatly deteriorated as compared with the above 4.0 TPI.

  Next, an S-twisted core wire and a Z-twisted core wire are alternately arranged on the back of the belt, and the S-twisted core wire has a twist number of 4.0 TPI and the Z-twisted core wire has a twist number of 3.7 TPI. In this case (difference in the number of twists = 0.3 TPI), the thrust force during driving could be reduced. Moreover, the bending fatigue property was also favorable. Therefore, it is considered that the thrust force at the time of driving can be made almost zero by creating a belt having a helical tooth angle with an inclination corresponding to the thrust force.

  Next, in the same way, when the S twisted core wire and the Z twisted core wire are alternately arranged, the twist number of the S twisted core wire is 4.0 TPI and the twist number of the Z twisted core wire is 3.0 TPI. (Difference in the number of twists = 1.0 TPI), the thrust force during driving was slightly larger than that in the above case where the difference in the number of twists was 0.3 TPI. However, the thrust force was smaller than the case where only the S strand core wire having a twist number of 4.0 TPI was arranged. Also, this belt was good from the viewpoint of bending fatigue. Therefore, if a belt having an inclined helical tooth angle corresponding to the thrust force (a helical tooth angle having a larger inclination than the case where the twist difference is 0.3 TPI) is created, the thrust force during driving can be made almost zero. Conceivable.

  The structure of the above embodiment can be changed as follows, for example.

  1. Instead of having the tooth portion tilted to the right and to the left when the belt running direction is the longitudinal reference as shown in FIG. 1, it is configured to have a reverse slope, that is, to the left and right as shown in FIG. Can do. In the case of FIG. 2, if the number of strands of the S-twisted core wire 4s is larger than the number of strands of the Z-twisted core wire 4z, the generated thrust force at the time of driving the belt can be reduced.

  The number of the core wires 4s, 4z,... Embedded in the back portion 2 is not limited to four as shown in FIGS. 1 and 2, and can be increased or decreased. Further, the number of strands of the S-twisted and Z-twisted core wires (difference in the number of twists of both core wires) and the helical tooth angle are not limited to those disclosed above, and may be larger or smaller than that. it can.

  Instead of alternately arranging the S-twisted core wire and the Z-twisted core wire, it is possible to embed a cord in which the S-twisted yarn and the Z-twisted yarn are twisted in the back portion. In this case, if a difference is made between the number of twists of the S-twisted yarn and the number of twists of the Z-twisted yarn, the thrust force due to the inclination of the helical teeth can be offset as described above.

  In the case of the above-mentioned stranded cords, when the inclination of the tooth portion 3 is rising to the left and falling to the left when the belt running direction is the longitudinal reference, the number of twists of the Z-twisted yarn is set to S-twisted yarn. If it is larger than the number of twists, the thrust force can be reduced. When the inclination of the tooth portion 3 is reversed, the number of twists of the S-twisted yarn may be increased and the number of twists of the Z-twisted yarn may be increased. Further, it is preferable that the belt is manufactured by changing the difference in the number of twists between the S-twisted yarn and the Z-twisted yarn according to the inclination of the tooth portion 3.

The schematic diagram of the helical toothed belt which concerns on one Embodiment of this invention. The schematic diagram of the helical toothed belt of another example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Belt with tooth tooth 2 Back part 3 Tooth part 4s S twisted core wire 4z Z twisted core wire 5 Lotus tooth C Belt axis (axis line along belt running direction)

Claims (10)

In a helical toothed belt comprising at least a back portion made of an elastic body in which a plurality of core wires are embedded, and a helical tooth portion,
In the back portion, the S-twisted core wire and the Z-twisted core wire are alternately arranged to be adjacent to each other,
The twist number of the core wire whose twist direction coincides with the twist direction of the tooth line of the tooth portion is different from the twist number of the core wire whose twist direction is opposite to the twist direction of the tooth line. , Lotus toothed belt. The helical toothed belt according to claim 1,
The inclination of the tooth portion is configured to rise to the left and to the left when the belt running direction is the longitudinal reference,
A helical toothed belt, wherein the number of twists of the Z-twisted core wire is greater than the number of twists of the S-twisted core wire. The helical toothed belt according to claim 1,
The inclination of the tooth part is configured to rise to the left and to the right when the belt running direction is the longitudinal reference,
The helically toothed belt, wherein the number of strands of the S-twisted core wire is larger than the number of strands of the Z-twisted core wire. In a helical toothed belt comprising at least a back portion made of an elastic body in which a plurality of core wires are embedded, and a helical tooth portion,
The core wire is made by twisting S-twisted yarn and Z-twisted yarn.
The twist number of the yarn whose twist direction matches the twist direction of the tooth of the tooth portion is different from the twist number of the yarn whose twist direction is opposite to the twist direction of the tooth streak. , Lotus toothed belt. The helical toothed belt according to claim 4,
The inclination of the tooth portion is configured to rise to the left and to the left when the belt running direction is the longitudinal reference,
The helically toothed belt, wherein the number of twists of the Z-twisted yarn is greater than the number of twists of the S-twisted yarn. The helical toothed belt according to claim 4,
The inclination of the tooth part is configured to rise to the left and to the right when the belt running direction is the longitudinal reference,
The helically toothed belt, wherein the number of twists of the S twisted yarn is greater than the number of twists of the Z twisted yarn. In a manufacturing method of a helical toothed belt comprising at least a back portion made of an elastic body in which a core wire is embedded, and a helical tooth portion,
In the back portion, a plurality of the core wires are alternately arranged and embedded so that the S-twisted core wire and the Z-twisted core wire are adjacent to each other,
The twist number of the core wire whose twist direction coincides with the twist direction of the tooth line of the tooth portion, and the twist number of the core wire whose twist direction is opposite to the twist direction of the tooth line, A method for manufacturing a helical toothed belt. It is a manufacturing method of the helical toothed belt according to claim 7,
While it is possible to manufacture a plurality of types of helical toothed belts having different helical tooth inclinations,
Depending on the inclination of the tooth part, the twist number of the core wire whose twist direction coincides with the twist direction of the tooth line of the tooth part, and twist of the core wire whose twist direction is opposite to the twist direction of the tooth line A method for manufacturing a helical toothed belt, wherein the difference from the number is changed. In a manufacturing method of a helical toothed belt comprising at least a back portion made of an elastic body in which a core wire is embedded, and a helical tooth portion,
In the back part, a core wire in which S twisted yarn and Z twisted yarn are twisted is buried,
The twist number of the yarn whose twist direction matches the twist direction of the tooth of the tooth portion is different from the twist number of the yarn whose twist direction is opposite to the twist direction of the tooth streak. The manufacturing method of a toothed belt with a lotus tooth. A method for manufacturing a helical toothed belt according to claim 9,
While it is possible to manufacture a plurality of types of helical toothed belts having different helical tooth inclinations,
According to the inclination of the tooth part, the twist number of the yarn whose twist direction matches the twist direction of the tooth line of the tooth part, and the twist number of the thread whose twist direction is opposite to the twist direction of the tooth line. A method for producing a helical toothed belt, characterized in that the difference is changed.

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